Home
Resources
Publications
Blue Phosphorescence With High Quantum Efficiency Engaging the Trifluoromethylsulfonyl Group to Iridium Phenylpyridine Complexes

Blue Phosphorescence With High Quantum Efficiency Engaging the Trifluoromethylsulfonyl Group to Iridium Phenylpyridine Complexes

Jin-Hyoung Kim, So-Yoen Kim, Seol Jang, Seungjun Yi, Dae Won Cho, Ho-Jin Son, Sang Ook Kang

Inorg Chem. 2019 Dec 2;58(23):16112-16125.

PMID: 31713415

Abstract:

Incorporation of an electron-withdrawing -SO2CF3 substituent to cyclometalating C^N-phenylpyridine (ppy) ligand resulted in an expected blue-shifted phosphorescence in the corresponding homoleptic Ir(ppySCF3)3 complex, showing the emission of λem = 464 nm at 300 K. One of its heteroleptic derivatives, modified by a pyrazolyl borate LX ligand, Ir(ppySCF3)2(bor), exhibited further blue-shifted phosphorescence of λem = 460 nm at 300 K. Cyclic voltammograms (CVs) and density-functional theory (DFT) calculations supported the efficacy of the electron-withdrawing capability of the SO2CF3 substituent lowering HOMO energy and obtained widened bandgaps and resumed blue emissions for all of the iridium complexes studied. The homoleptic complexes of both substituents, Ir(ppySCF3)3 and Ir(ppySF)3, reached the higher quantum yields (ΦPL) of (0.89 and 0.72), respectively. Similarly, emission quantum yields (ΦPL) of the heteroleptic derivatives were reported to be (0.75, 0.83, and 0.87) for Ir(ppySCF3)2(acac), Ir(ppySCF3)2(bor), and Ir(ppySCF3)2(pic), respectively. Emission kinetics support the enhanced quantum efficiency when kr and knr values are compared between Ir(ppySCF3)3 and Ir(ppySF)3, and both values favorably contribute to attaining a higher quantum efficiency for Ir(ppySCF3)3. Among solution-processed multilayered devices having an ITO/PEDOT:PSS/TCTA:Ir dopant (10:1, w/w)/TmPyPB/Liq/Al structure, a heteroleptic dopant, Ir(ppySCF3)2(bor), exhibited better device performance, reporting an external quantum efficiency (EQE) of 1.14%, current efficiency (CE) of 2.31 cd A-1, and power efficiency (PE) of 1.21 lm W-1, together with blue chromaticity of CIEx,y = (0.16, 0.32).

Chemicals Related in the Paper:

Catalog Number	Product Name	Structure	CAS Number	Price
AP921205030	TmPyPB		921205-03-0	Price

As a specialist in analytical chemical Products, Alfa Chemistry offers consumers a wealth of raw materials and a full range of technologies and services.

QUICK LINKS

HEADQUARTERS

Tel:

Fax:

Email: